Rheem · Furnace

22 Main limit open

High severity Rheem/Ruud 802P / 80MDP 80% two-stage furnace (UT 1028-928 IFC)R95PRGPE/RGLE

What the control is telling you

Main high-limit circuit is open (supply air too hot / poor airflow). 802P/R95P: if open more than 150 seconds during a heat call, 61 and 22 alternate (dead blower) until it recloses. RGPE/RGLE: an open main limit can indicate excessive duct static; thermostat shows Call For Service / CHECK FURNACE.

Applies to: 802P/80MDP (802PA050-150); R95P (R95PA040-115); RGPE/RGLE 2-stage 80+

Likely causes

Dirty or restricted filter or cooling coil
Closed registers/dampers, undersized or restricted ducts, high static
Blower problem: wrong speed tap, bad capacitor, dirty wheel, failing motor, low voltage
Overfiring (high gas pressure, wrong orifice)
Loose limit wiring

Test and repair steps

Replace the filter and check the A/C coil and blower wheel for dirt.
Check registers/dampers are open and ducts are adequate.
Verify the blower runs on heat speed; check speed tap, capacitor, wheel and motor (RGPE/RGLE: ECM blower, see 60/61).
Measure temperature rise and compare with the rating plate range.
RGPE/RGLE check rise at both low and high fire; adjust SW3-1/SW3-2 heat rise if outside range.
Check manifold pressure and orifice size for overfiring.
Check wiring between IFC and all limits; replace a limit that is open at normal temperature.

Settings for these units

Clearance to combustibles (all models) · R95P

Location	Minimum clearance
Left side	0 in.
Right side	0 in.
Back	0 in.
Top	1 in.
Front	2 in.
Vent	0 in.
Service (front)	24 in. recommended

Same values for R95PA040 through 115.

Column order read from a rotated drawing header - confirm on the furnace clearance label.

Filter sizes as shipped, upflow (Table 19) · RGPE/RGLE

Cabinet width	Input	Bottom filter	Side filter	Quantity
17-1/2 in.	50, 75 (000 Btu/h)	15-3/4 x 25 in.	15-3/4 x 25 in.	1
21 in.	75, 100 (000 Btu/h)	19-1/4 x 25 in.	15-3/4 x 25 in.	1
24-1/2 in.	125 (000 Btu/h)	22-3/4 x 25 in.	15-3/4 x 25 in.	1

Use one filter location only - do not double-filter or filter the supply side.

21 in./100K: cut 3-1/2 in. off filter and frame for a side filter; 24-1/2 in./125K: cut 7 in.

Reduced clearance to combustibles, upflow/horizontal (Fig. 4) · Rheem/Ruud 802P / 80MDP 80% two-stage furnace (UT 1028-928 IFC)
Reduced clearance to combustibles (Fig. 3 and 4) · RGPE/RGLE

Models that show this code

21 models in Rheem/Ruud 802P / 80MDP 80% two-stage furnace (UT 1028-928 IFC), R95P, RGPE/RGLE

R802PA050314MSAR802PA075417MSAR802PA100521MSAR802PA125524MSAR802PA150524MSAR95PA0401317MSAR95PA0601317MSAR95PA0701317MSAR95PA0851521MSAR95PA1001521MSAR95PA1151524MSARGLE-05(-)BMKRRGLE-07(-)AMKRRGLE-07(-)BRQRRGLE-10(-)BRMRRGLE-12(-)ARMRRGPE-05(-)BMKRRGPE-07(-)AMKRRGPE-07(-)BRQRRGPE-10(-)BRMRRGPE-12(-)ARMR

Other codes on the same units

12 Low flame sense
13 Flame lost
14 Unexpected flame
20 Twinning fault
23 HALC limit open (HALC LIMIT OPEN)
26 Line and neutral reversed
33 Rollout switch (MRLC) open
44 Low pressure switch closed (stuck)

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Source: 802P: 92-24161-146-02, Diagnostics and Fault Codes table, p.40, 48, 51; R95P: Diagnostics and Fault Codes table, p.87 (PDF p.91); RGPE/RGLE: Table 16 p.49 / Table 20; Fig. 45 p.63; user menus p.52. Summarized in our own words; check the original manual for your model.

Homeowner looking at this code? See what it means for you and when to call a technician.

For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.